Shell-grinding machine.



F. DI GIANNI.

SHELL GRINDING MACHINE.

APPLICATION FILED JAN.27,1913.

1,0855381. Patented Jan. 27, 1914.

4 4 unmnumuqmm .4 6 J g f l Hm f/i'zifm WITNESSES ported thereby abovethe upper surface of hurrah. strarss PATENT orr on.

FRANK DI GIANNI, ORMUSCATINE. IOWA, ASSIGNOB T0 MUSCATINE REARL NOVELTYCOMPANY, OF MUSCATINE, IOWA, A CORPORATION OF IOWA.

SHELL-GRINDING mnorx nn.

oeaasr Specification of Letters Eatcnt.

Patented Jan. 27, 1211s.

Application filed January 27, 1913. Serial No. 745,422.

To (ZZZ whom it may concern:

Be it known that- I, FRANK DI Guxxr, of Muscatine, in the county ofMuscatine and State of Iowa, have invented certain new and usefulImprovements in ShellGrimling Machines; andI hereby declare that thefollowing is a full, clear, and exact description I thereof, referencebeing had to the accoml pan ing drawings, which form part of thisspecification.

This invention is a novel machine for grinding pieces of shell and thelike in irregular form. it being especially designed for use in grindingpieces of pearl shell into brooches, pins. fobs, buckles, and otherornamcntal articles.

The invention consists in the novel construction of the means forpresenting the shell to the grinder so that itcan be ground I to thedesired form without any particular attention on the part of theoperator other than to rotate the shell support so as to present theshell edgcwise to the grinder; and such means is illustrated in theaccompanying drawing and hereinafter described.

In said drawings-Figure 1 is a top plan View of the shell grindingmachine, partly broken away. Fig. :2 is an end elevation of Fig. 1,partly broken away. Fig. 3 is a detail section on line 3--3, Fig. 1.Fig. l is a detail View of one of the cams.

The machine comprises -a head plate 1, which preferably formed with alongitudinal dove-tailed groove. in its upper side, in which groove ismounted a slide 2, and said slide is normally projected outwardly bymeans of a spring 2 interposed between the outer end of the side and acap plate 1* at ached to the outer end. of the plate 1 as shown.Attached to said slide, and supthe plate 1, is a transverse bearing 2-for a shaft 3; and this shaft may be removably secured in position inthe bearing 2 by having "the cap-plate 2 detachably secured to the basebearing plate by tap bolts so that by removing the cap-plate 2 theshaft- 3 can be bodily rem'oved from the bearing. This shaft 3 isprovided, preferably at each end of the bearing, with a cam-3. Thesecams correspond in external contour to the external contour which it isdesired to 1mpart to the shell object. As illustrated the cams are ofshield-shape and the shell S will be reduced to a similar shape, as

cated by the dottedline's Fig. In practice interchangeable sets of cams3 2 of (lllltlllll shapes may be prov ded, one cam or of cams for ea cshape of shell which it- IS desired to produce'by-the machine; such camsmay be detachabl'y. at

tached to the shaft 3 in any well known manner; or if desired the camsmay be per manently attached to shafts 3, and siich cammed shafts beinterchangeable. I T he peripheries of the said cams 3 are adii ted.

I it to move against such spring.

One end of the shaft may be provided with a shell clamp 3 of anysuitable construction, to hold a piece of shell S parallel with the cams3 and perpendicular to the shaft 3. Ordinarily the piece of pearl orshell to be shaped hasan opening through it, which opening correspondswith a stud 3 on the clamp head and the shell S is held endwise againstthe clamp by means of a screw 3, or in any other convenient way. Theparticular means for clamping; the shell to the shaft 3 is not a featureof the invention.

Adjacent the clamp 3 is a grinder 5, which may be of carlmrundum orother suitable material. mounted on a spindle :3 which can be driven bya belt 5. or in any other suitable manner. The shaft 3 may he rotat edmanually by means of a handle 23".

The slide 9 may be retracted by means oi a lQVQ-I. fl pivoted at- 6 uponthe standard 1 on which plate 1 is supported; and lever 6 may beoperated by hand. or may be connected by a rod 6 to a trcadlc lever, notshown, so that it can be. operated by the foot when it is desired toretract the slide Qand withdraw the shell from the grinder 5, againstthe resistance. of spring 2". The standard I and the spindle of thegrinding wheel 5 may be mounted upon a base 7 in any suitable way, so asto hold the said parts in relatively fixed relation.

Operation: When the parts are in the poand she sition indicated in Fig.1, and a shell S at tached to the end of the shaft 3, said shell will bepressed edgewise into contact with the grinder by the action of'thespring 2 5 on the slide 2, which slide moves the shaft cam and shellbodily, as indicated in the drawing. The movement of the slide will bearrested first by the contact of the edge of the shell with the grinder5; but as the grinder is rotatedthe shell is cut away and the slideadvances the shell toward the cutter until the forward movement of theslide is arrested by contact of the cam or cams 3 with rollers 4. Theoperator should turn shaft 3 slowly, by means of the handle 3, v andthus present the entire edge of the shell to the grinder, and the lattercuts away the :shelluntil it conforms in shape to the shape 7 of thecams, as will be readily understood 2.0 from the drawing. The piece ofpearl or shell S attached to clamp 3 is perferably roughly shaped,beforeit is attached thereto so as to reduce the time and amount ofgrinding required. i

# It will be seen that by having interchangeable cams, or shafts andcams, the shells may be cut of any desired form or outline; when theoperator can rotate shaft 3 without any further firinding contactbetween the grinder the work iscompleted, and the shell will be of theform of the cams; then by depressing the lever 6 the slide 2 isretracted, moving the finished shell away from the grinder, and'anotherpiece of shell can be operated upon. The cams, or cams and shaft, can beremoved and substituted by others to produce the desired shape of shell.

What I claim is: v

The'combination with a support, a grinder rotating on a vertical axis, aslotted plate on said su port, a slidemovably mounted in the slot 0 saidplate, a manually rotatable changeable shaft mounted horizontally on andtransversely of said slide, a pair. of cams fizied on said shaft atopposite sides of the slide, members attached to the support adjacentthe slide and engaging said earns, a clampon the outer end of said shaftfor securing a shell thereto; a spring engaging said slide to cause theshaft to yieldingly' hold the shell against the grinder, and a lever andconnections for retracting said slide,

substantially as described.

In testimony that I claim the foregoing as I my own, I affix mysignaturein presence of two witnesses.

FRANK DI GIANNI. l/Vitnesses PAUL S. BAKER, OWEN E. VA CE;

